Some communications protocols may use adaptive modulation (also known as adaptive bit loading), wherein the modulation type can vary by sub-carrier. This may occur, for example, with respect to communications using the sub-carriers in various orthogonal frequency-division multiplexing (OFDM) systems. Thus, when adaptively modulated data, which may include packets, is sent to a receiver, a question may arise: Should the modulation used in conjunction with the communication be indicated as well (e.g., should the data be self-defined), or should the data be sent without indicating the modulation type (e.g., should the data be non-self-defined)? Transmitting self-defined data may incur greater on-air overhead. On the other hand, sending non-self-defined data may require several assumptions about the receiver state.